Piperine for the treatment of vitiligo

Vitiligo, a skin pigmentation disorder, which afflicts an estimated 100 million people worldwide, is characterized by the loss of pigment in affected areas of skin. It is the disease that pop star Michael Jackson publicly disclosed that he had. It is neither life threatening nor contagious. But the sometimes unsightly white patches it causes produce emotional distress for many and often lead to social ostracism because of a widespread misperception that the condition is infectious.

An estimated one to two percent of the world’s population, or 60 to 100 million people, suffer from the malady. Current treatments, which rely on immunosuppression or ultraviolet radiation to stimulate repigmentation, are only partially effective, often producing a mottled appearance. Excessive UV radiation also poses the risk of skin cancer.

Images courtesy of the Vitiligo Society, UK

A Potential New Treatment for Vitiligo

The Department of Dermatology is pleased to announce that it is supporting scientific research by Amala Soumyanath, Ph.D., an associate professor in the Department of Neurology, and Philippe Thuillier, Ph.D., an assistant professor in the Department of Public Health and Preventative Medicine, for their promising work on a new potential vitiligo therapy. The OHSU Department of Dermatology selected these investigators based on strong preliminary data supporting a role for piperine in the treatment of vitiligo. Piperine, an extract of black pepper, has been demonstrated to enhance melanocyte growth in vivo. The goal of this innovative research is to offer people with vitiligo a new and effective treatment option.

“Based on the animal studies we have done, these compounds, if proven safe in humans, promise far superior results in the treatment of vitiligo than current approaches,” said Amala Soumyanath, Ph.D. “Vitiligo is a highly visible disease that can greatly affect patients psychologically and emotionally, even driving some to consider suicide. Any breakthrough in treating it would benefit a huge number of people around the world.”

Piperine Stimulates Skin Pigment Cells

Soumyanath and her collaborators reported on the effects of their compounds in animals in a paper published in the British Journal of Dermatology. But development of the concept dates back more than a decade (click here to read Soumyanth’s story of the discovery of piperine). Soumyanath discovered –in research on vitiligo that she initiated at King’s College London – that piperine, the alkaloid in black pepper responsible for its pungency, stimulated the proliferation of melanocytes in cell cultures. Melanocytes are the cells that produce pigmentation in the skin. The researchers then designed and tested many synthetic piperine analogs and identified a number that produced the same result.

The group subsequently found that piperine and two of its analogs – tetrahydropiperine (THP) and a cyclohexyl derivative (RCHP) produced light, even pigmentation when applied to the skin of a poorly pigmented mouse model. When combined with UV radiation, the skin grew significantly darker and showed none of the patchiness caused by UV treatment alone. Moreover, skin pre-treated with a piperine compound required fewer UV exposures, thus lowering the cancer risk, and it took longer for the pigmentation to fade again than when UV alone was used.

Piperine and Skin Pigment Cells

Melanocytes are seen as dark squiggly cells (see arrows). Piperine treatment increases the number of melanocytes ( B vs A) while adding UV increases the number of melanocytes and their pigment production, making them look darker (see cell indicated with arrowhead in C. (Circular structures are hair follicles).

Piperine Research at OHSU

Soumyanath came to OHSU in 2003, where she has established collaborations with scientific and clinical researchers to continue work on this project. “Dr. Soumyanath’s discoveries open up completely new and exciting treatment possibilities for those individuals affected by vitiligo,” said Sancy Leachman, M.D., Ph.D., professor and chair of dermatology at OHSU and one of Soumyanath’s recent collaborators. “There is a huge unmet need for this disease, since we have very few treatments to offer patients right now,” she noted.

Soumyanath and Thuillier are continuing to find additional scientific answers. The next step before clinical trials can be undertaken in the U.S., said Soumyanath, is to determine whether the repigmentation effects of piperine is associated in any way with melanoma or other skin cancers. “From our mouse and cell studies so far, it doesn’t appear that is the case,” she said, “in fact, piperine seems to have anti-cancer or cancer preventive effects. We are hopeful that more detailed research will bear this out.”

OHSU acquired the patents to Soumyanath’s piperine compounds from King’s College London and BTG International Ltd. in 2006, and is actively seeking a commercial partner to advance piperine through pharmaceutical development. In the meantime, the researchers are actively seeking grants and philanthropic donations to obtain data to attract such a partner.